Ignition system



y 1934- J. L, ARTHUR 1,957,127

IGNITION SYSTEM Filed March 25, 1931 Patented May 1, 1934 1.951.121 IGNITION SYSTEM James- L. Arthur, Anderson, Ind., assignor, by mesne assignments, to General Motors Corporation, Detroit, Mich, a corporation of Deiav ware Application March 25, 1931, Serial No. 525,247

4 Claims. (01. 29o -3'z This invention relates to ignition apparatus for internal combustion engines and more particularly to ignition apparatus of the type operated by a storage battery used also to supply 5: current to an electric motor for starting the engine.

In an electric system for engine starting and ignition where a. storage battery is employed for supplying current for ignition and starting purposes at the same time the voltage impressed by the battery upon the ignition system is lower than during the normal running of the engine. Under these conditions it is more diflicult to start the engine especially in cold weather when the drain on the battery for cranking current is heavier. In order to overcome this difliculty engine starting and ignition systems have been provided in which an ignition regulating resistance is employed in series with the primary winding of 'the ignition coil in order to control the flow of current in the ignition circuit. Usually this resistance element is made of a metal such as iron the resistance of which increases as the temperature increases. In this way the current in the ignition circuit is automatically regulated so that it will not be excessive in the low speeds, when the period of timer contact closing is rela-' tively long, but so that at high speeds, when the time of contact closing is relatively short, there will be suillcient current for ignition purposes.

In order to provide sufllcient current for ignition while the electric starting motor is draining the battery the ignition regulating resistance is cut out or short circuited in prior devices by a switch operated in conjunction with the starting motor switch.

It is an object of the present invention to provide means for controlling the operation or the ignition regulating resistance inv a way that does not require the modification oi the starting motor switch, and. in the disclosed embodiment of the present invention this aim is accomplished by means responsive to the connection of the battery charging generator with the battery when 45 the engine which drives the generator has attained a certain speed. This automatic connection oi'the generator and battery is usually eflected by a reverse current relay or cut out relay which automatically completes the 50 charging circuit when the generator'voltage has attained a certain value and which automatically disconnects the starting circuit when the generator voltage ialls below a predetermined value such that there is a reversal of direction or cur- 55 rentflomthobatterydischormintothegenerator. In my improved system the ignition regulating resistance is normally short circuited so that it is inoperative to reduce current flow while the starting motor is operating to crank theenglue. The short circuit of the ignition regulating so resistance is automatically interrupted when the cut out relay operates to connect the generator with the battery.

Further objects and advantages of the present invention will be apparent from the following as description, reference being bad to the accompanying drawing, wherein a preferred embodi ment of'one form of the present invention is clearly shown.

In the drawing:

Figs. 1 and 2 are wiring diagrams of two difvferent forms of the present invention.

Referring to Fig. 1, battery 20 groimded at 21 is connected by a switch 22 with a starting motor 23 grounded at 24. The battery 20 is also connected by an ignition switch 29 with an ignition coil 30 having a primary winding 31 and a secondary winding 32. The ignition regulating resistance 33 connects the primary 31 with terminal 34 of an ignition timer 35 which comprises a cam 36 operating upon a circuit breaker lever 37 carrying a movable contact 38 engaged with a stationary contact 39 grounded at 40. A leaf spring conductor 41 carries the terminal 34 with the circuit breaker lever 37 and operates to urge the circuit breaker lever rubbing block 42 toward the cam 36 and the contact 38 toward the contact 39. The secondary coil 32 is connected with a contact 45 of a distributor 46 having a rotor 4'7 rotatable past a circular row of contacts 48 connected with spark plugs 49.

The ignition regulating resistance 33 is normally short circuited by a pair of contacts 50 and 51. The contact 50 is attached to armature lever 52 pivoted at 53 and urged by a spring 54 toward the contact 51. The armature lever 52 cooperates with an electro-magnet or relay coil 55 which is connected in series with a generator 56 grounded at 57 and with the series coil 58 of a cut-out relay 60 having also a voltage responsive coil 59. 100 The coil 58 is connected in series with a pair of contacts 61 and 62, the latter being carried by an armature lever 63 hinged'at 64 and normally urged by spring 65 against a stop 66. In this position the contact 62 is separated from the con- 105 tact 61. The armature lever hinge 64 is connected by wire 6'7 with the battery 20.

Inthe engine ignition and battery charging system shown in Fig. 1, the ignition regulating resistance 33 is normally short circuited so that 10 during the operation of the cranking oi the en-' gine with the electric motor 23 (rendered operative by closing switch 22) the voltage capable of being impressed by the battery upon the ignition primary 31 will'not be reduced by a voltage drop across the terminals or the resistance 33. When the engine becomes seli operative and the voltage impressed upon the relay voltage coil by the generator exceeds a certain value the relay contact 62 will be attracted into engagement with the contact 61 thereby connecting current responsive magnet coils and 58 in series with the generator and battery. When this occurs the armature lever 52 will be attracted toward the coil 55 thereby separating the contact 50 from the contact 51. Thereafter the regulating resistance 33 is operative to regulate the flow of current through the ignition primary winding.

In the form of invention shown in Fig. 2 the ignition regulating resistance 33 is normally short circuited by wires and 71 connected respectively with contacts 73 and 72 bridged by a contact 74 attached to a non-conducting block 75 carried by the armature lever 63 01 the cut out relay 60. Hence as in Fig. 1 the ignition reg ulating resistance 33 is inoperative while theengine is being cranked. When the relay 60 operates to close contacts 61 and 62 and connect the generator with'the battery by the movement of armature lever 63, the contact '74 will beseparated from the contacts 72 and 73 thereby interrupting the short circuit around the resistance 33.

Where the electric system forautomotive vehicles includes an ignitionfcoil mounted upon the dash board of the vehicl'efthe form of invention shown in Fig. 1 is adapted to be used since the relay 55 can be conveniently mounted on the instrument board in proximity to the ignition coil. In some installations where the ignition coil is mounted with the cut out relay upon the generator frame, the form of invention shown in Fig. 2 can be conveniently used without complicating the wiring of the system.

While the form of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other ,iorms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. An electric ignition system for internal combustion engines comprising, in combination, an ignition circuit including an ignition primary winding, an ignition regulating system and an ignition timer connected in series, an electric starting motor, a storage battery Ion operating the starting motor and ignition, a generator for charging the storage battery and for supplying ignition current while the engine is a relay for automatically connecting the generator and battery at a certain generator voltage and for disconnecting the generator from the battery when the generator voltage passes below a certain value, a switch normally operative to render the ignition resistance inoperative, and an electro-magnet rendered operative by the closing of the relay contacts for controlling said switch in order to render said ignition resistance operative to the running or the engine.

2. An electric ignitionsystem for internal combustion engines comprising, in combination, an ignition circuit including an ignition primary winding, an ignition regulating system and an ignition timer connected in series, an electric starting motor, a storage battery for operating the starting motor and ignition, a generator for charging the storage battery and for supplying ignition current while the engine is running, a relay for automatically connecting the generator and battery at a certain generator voltage and for disconnecting the generator from the battery when the generator voltage passes below a certain value, a switch normally short circuited to ignition resistance, and an electro-magnet having a winding in series with the contacts of the cut-out relay whereby the ignition resistance circuit switch will be opened when the relay contacts close.

3. In an electrical system for internal combustion engines, the combination with an ignition system comprising a generator, a starting motor,

a battery for operating said starting motor and ignition system, a resistance element in said ignition system, a switch normally closed to render said resistance element non-operative, a relay for automatically connecting said generator and battery at a' certain generator voltage and for disconnecting said generator from the battery when the generator voltage passes below a certain value, and an electromagnet rendered operative by the closing of said relay contacts for controlling said switch in order to render said resistance element operative on the closing of said relay contacts.

4. An electric ignition system for internal combustion engines comprising, in combination, an ignition circuit including an ignition primary winding, an ignition regulating system and an ignition timer connected in series, an electric starting motor, a storage battery for operating the starting motor and ignition, a generator for charging the storage battery and for supplying ignition current while the engine is running, and means responsive to the flow of current from the generator to the battery for open-circuiting an ignition resistance, said means including an electro-magnetic device having a magnet coil in-the battery charging circuit.

I JAMES L. ARTHUR. 

